Enrichment Of Anaerobic/Aerobic Biofilm Alternating Conditions Of Phosphorus In Waste Water

In order to solve the problem of phosphorus pollution and phosphorus resource shortage in wastewater,a new hanging nylon biofilm reactor was developed to simultaneously remove and enrich the phosphorus in sewage,and to study the properties of phosphorus removal and phosphorus storage.In the first stage,a novel biofilm reactor was adopted to treat synthetic wastewater,and the feasibility of cultivating and enriching a high concentration of PAOs in this conventional biofilm within a short time was investigated,which proved by reactor's operational efficiency,the rate of phosphorus removal and the condition of PAOs enrichment..After enrichment,the enrichment process of PAOs enters into the second stage,and the high-concentration phosphate recovery solution is obtained through continuous enrichment in the anaerobic stage,the enrichment process and the influence of various factors are discussed.Research indicates:(1)Under the conditions of influent phosphorus concentration of 5mg / L and COD concentration of 200 mg / L,the removal rate of orthophosphate in aerobic stage was more than 95% and the effluent concentration of COD was 50 mg · L-1 below,also,the stable operation of the treatment level for 50 days.(2)After 48 d of operation,the reactor's phosphorus uptake rate and release rate were increased from 3.4 mg·(L·h)-1 and 3.4 mg·(L·h)-1to 8 mg·(L·h)-1and 6 mg·(L·h)-1,respectively,and the aerobic and anaerobic cycle was shortened from 6h and 6h was shortened to 2h and 3h,respectively.,the operating efficiency was significantly increased.(3)The enrichment of phosphate accumulating bacteria in sludge was increased from 48.96% to 70% by fluorescence in situ hybridization(FISH)after 50 days of culturing.The PAOs in hybridization map appeared in large aggregates,Biofilm culture is near to maturity.By hardening culture for 50 d,a high concentration of 70% in full organisms of PAOs can be enriched in the conventional nylon filler,which make the reactor has a high efficiency in removal of phosphorus and organic matter in sewage.(4)In the aerobic stage,the water conditions remain unchanged and phosphorus removal efficiency can reach 95% or more,to meet the effluent in the 0.5mg / L below;after nearly two months of enrichment,to obtain concentration of phosphorus about 60 mg / liquid.(5)when the anaerobic reactor COD reached 1200mg/L,the concentration of phosphorus recovery solution was sudden to 80mg/L.When stop adding carbon and COD concentration returned to normal,the concentration of the recovered liquid was reduced to 60mg/L,the subsequent stability in the value of that biofilm on the phosphate-rich phosphorus solution in phosphorus release threshold,need to exert a certain degree of stimulation to stimulate the release of more phosphorus on the biological,phosphorus-rich solution Concentration.(6)The content of total phosphorus in dry mud is about 167.2mg / g,which is much higher than that in the activated sludge process.Experiments show that the anaerobic / aerobic biofilm system can effectively recover the phosphorus-rich solution on the basis of efficient phosphorus removal,and remove and enrich the phosphorus solution at the same time.